79 



Obione of Gsertner. The total number of species enumerated 

 is 347, arranged in 2 suborders, 7 tribes, and 46 o^enera. 



A Flora of North America, arranged according to the Natural System, by 

 John Torrey and Asa Gray. Vol. i. parts 3 and 4. 



At pages 5 and 41 of the volume of this work for 1839, 

 this important publication has been already noticed. Since 

 that time two more parts, completing the first volume, have 

 made their appearance. They contain the remainder of 

 Leguminosse, and all the orders as far as Loranthacese inclu- 

 sive, of DeCandoUe's Prodromus, embracing therefore some 

 of the most extensive of the orders commonly cultivated in 

 gardens. 



The work is so full of original and valuable matter that to 

 make extracts is an endless labour ; all persons interested in 

 the North American Flora will of necessity procure the book 

 itself. The reviewer must confine himself to general ob- 

 servations upon points to which special attention should be 

 drawn. 



The authors have bestowed much pains upon extricating 

 the entangled synonymy of garden plants long cultivated 

 in European gardens, and the opportunity enjoyed by Dr. 

 Gray of examining, when in Europe, the original authorities 

 upon which numerous species have been founded, gave him 

 such advantages as no previous American Botanist has ever 

 possessed. That he has used such opportunities with profit 

 will not be doubted by any one who knows his Botanical skill 

 and peculiar aptitude for critical investigation. We are how- 

 ever clearly of opinion that in reverting at all times to the first 

 name that has been given to a particular species he occasion- 

 ally sacrifices general convenience to chronological rigour. 

 For instance, it appears that the name Crataegus tomentosa 

 was given by Linnaeus to the plant now universally called 

 C. pyrifolia ; and consequently the former name is restored ; 

 but surely this is precisely one of the cases where smnmum 

 jus is summa injuria, for the efi*ect of the alteration is to 

 render the nomenclature of every writer upon American trees, 

 with the solitary exception of Duroi, at variance with that of 

 the work now in course of publication. Had Linnaeus given 

 such a description of his plant as would have enabled Bota- 

 nists to know what he meant, the name of C. pyrifolia would 

 not have been substituted ; but he did no such thing ; he 



